Retired soldier Mr Lai at first volunteered to try to talk Mr Chen down but was turned away by police, Xinhua said.
Mr Lai is said to have then broken through the police cordon, climbed to where Mr Chen sat, greeted him with a handshake - and then pushed him off the edge.
Pictures in the China Daily show him saluting to the crowd after Mr Chen fell on to the partially filled emergency air cushion.
"I pushed him off because jumpers like Chen are very selfish," the newspaper quoted Mr Lai as saying.
"Their action violates a lot of public interests. They do not really dare to kill themselves. Instead, they just want to raise the relevant government authorities' attention to their appeals."
We should be checking if this guy has any links to the UK, even if he;s even spoken to a Brit, make his PM!! Perhaps he can help some of the money pilfering cnuts to meet their end. Oviously making sure to tax their families into destitution with the inheritance smash!